Optical discs, such as digital video discs (DVDs) and compact discs (CDs) provide a convenient and low cost means for data storage.
Optical discs are sometimes referred to as WORM (write once, read many) storage discs. This refers to the property of these storage devices (and their associated media) allowing data to be written once, and then be physically incapable of being re-written. WORM is especially useful for archival storage and data backup. Because WORM media cannot be written over, the media can not be erased (either inadvertently or deliberately) and the data would be more secure. Such security lends itself to reliable archive of data, as might be required in legal fields, historical archiving, and medical data storage. Data destruction requires destruction of the media, which would be apparent to observers. In addition, security features can be added to the system allowing for greater data security. For example, a universal identification number can be associated with each disc or data block. Alternatively, another identification number, bar code, checksum or other identifier could be associated with an optical media device, allowing detection of disc removal and replacement. Further, the recorded data can be protected, for example by encryption. With such solutions, archival data can be made quite secure.
Data centers have a need for processing large amounts of data. Such data would need to be stored in a secure manner. Optical discs provide one method of secure storage of a large amount of data. A single layer digital video disc can store 5 GB of data on a standard 12 cm disc. Higher density formats, such as Blu-ray, allow storage of up to 50 GB of data on a single storage disc. This massive storage capacity can be leveraged by an automated library system that would allow parallel read/write operations, and robotic disc handling to allow maximized throughput of the desired processes.